Leonard Finkelman
It is a time of discovery.
Using new technologies, human
scientists stand on the verge of cloning
extinct organisms.
Meanwhile, in a distant galaxy, the last of the
ZILLO BEASTS has died at the hands of the Jedi.
In an effort to harness the beasts' terrifying power, the evil
Sith Lord Darth Sidious has ordered that the species be resurrected
through cloning.
Against these attempts at DE-EXTINCTION, rational thinkers urge caution,
turning to philosophy to restore order to both galaxies.…
A long time ago, on the far, far away planet of Malastare, legends were told of humongous monsters known as the Zillo Beasts. With a massive, snake-like body covered in protective horns, five dexterous limbs, a spiked tail, and a mouth filled with razor-sharp teeth, a single Zillo Beast had the capacity to level an entire city by itself. The planet's children would be warned: don't wake the Zillo Beast! They needn't have worried. All the Zillo Beasts were supposed to be dead.
That was before the Clone Wars, when Republic forces awoke a very much alive and angry Zillo Beast – the last of its kind.1 It was before that last Zillo Beast caught the attention of Darth Sidious, who wanted to harness the monster's terrible destructive power. It was before Lord Sidious, in his guise as Supreme Chancellor Palpatine, ordered his top scientists to clone the beast after it was killed and the species was finally driven to extinction.2 The Zillo Beasts had gone extinct – really, this time – but might they awaken again?
Cloning was a common practice in that distant galaxy, where entire clone armies were grown and trained to fight wars across star systems. A young clone named Boba Fett gained notoriety as the galaxy's most feared bounty hunter.3 In the Unknown Regions beyond the galaxy's outer rim, the Chiss tactical genius Mitth'raw'nuruodo – who would later become Imperial Grand Admiral Thrawn – hatched a plan to clone himself so that his legacy might live on beyond his potential death.4 One might wonder if the Zillo Beasts could be cloned, but it seems more appropriate to wonder why the Zillo Beasts hadn't been cloned yet.
On our planet, the question of whether or not an organism can be cloned is more difficult to answer. Cloning technology remains in its infancy; nevertheless, success seems inevitable. Following the production of the first viable engineered clones, scientists are already asking: can we resurrect Earth's extinct species? Might the woolly mammoths wake again? The reawakening of extinct species, or “de-extinction,” has gained massive popular appeal. Tens of millions of dollars have already been spent on attempts to clone extinct organisms, but it's not yet clear that this has been money well spent.
Julian Baggini has said that philosophy is what we have left to discuss after we agree on all of the facts.5 Imagine, then, that Republic scientists succeed in cloning a Zillo Beast: what questions would be left to ask? It might be a fact that the clone looks like or behaves like a Zillo Beast, but it turns out that neither of those facts can tell us if the clone actually is a Zillo Beast. It takes a scientist to say whether we can clone extinct organisms, but it takes a philosopher to say whether cloning can actually reawaken extinct species.
Philosophers sometimes use far-fetched examples to answer the questions that are left after we agree on all the facts. These “thought experiments” are meant to show us what we really believe: that is, which ideas we're willing to hold on to when we push those ideas to their logical limits. So let's take the idea of de-extinction to a galaxy far, far away: when the stars are already overrun with clones, are we still willing to defend the idea that extinct species can be reawakened? Some astro-droids may think that philosophers are mindless, but we'll show those overweight globs of grease how philosophy can contribute to the development and understanding of science and technology.
We need to agree on some facts before delving into the philosophical debate over de-extinction. Let's start with the obvious: what is a clone? Very simply, a clone is any organism that's genetically identical to another organism. Technically, the first clones we encountered in the Star Wars galaxy were the Tonnika Sisters – a pair of identical twins who were in the Mos Eisley cantina when Luke Skywalker and Obi-Wan Kenobi first met Han Solo and Chewbacca.6 But technicalities are rarely satisfying, as anyone who's dealt with a protocol droid can attest. When we talk about clones, we normally don't have naturally born identical twins in mind.
Human scientists generally claim that the most famous clone on Earth is a sheep named Dolly, created by Scottish geneticists in 1996,7 but Star Wars fans know better. The most famous clone on this or any other world is the bounty hunter Boba Fett, created by the skilled cloners of Kamino to be an exact genetic duplicate of Boba's “father,” Jango Fett. Boba and Dolly are clear examples of what really comes to mind when we think of clones: not just genetic duplicates, but genetically engineered duplicates.
Both the Scots and the Kaminoans engineered their clones in the same way. They used a method known as somatic cell nuclear transfer (SCNT). All vertebrate organisms have two fundamentally different kinds of cell in their bodies. Germ cells (sperm and eggs) have nuclei containing half of the organism's genetic code: these cells combine with another organism's germ cells to create a new, genetically distinct embryo during sexual reproduction. Once it has a full complement of genetic material, the embryo starts to create somatic (body) cells. All somatic cells are descended from an original collection of stem cells. Stem cells in different parts of a developing embryo will use different parts of the same genetic code, such that a stem cell in one part of the developing body becomes skin while another in a different part of the body becomes hair. Since they all start with the same full set of genetic instructions, each somatic cell has a nucleus containing all of the organism's genetic code.
Suppose that we take a nucleus from one of these somatic cells and microsurgically implant it, with its full complement of genetic material, into an egg whose nucleus' original genetic material had been removed. This transfer creates an embryo similar to one created by sexual reproduction. The embryo will eventually grow into a genetically identical twin of the somatic cell's original owner. That's how SCNT creates clones. In principle, SCNT should work with a nucleus taken from just about any of a body's somatic cells.8 But no one ever said that the body had to be living or from a living species. Darth Sidious knew this when the last Zillo Beast died and left a heap of somatic cells lying outside the Republic Senate chambers. Human scientists know this as well and are recovering genetic material from extinct species, as they did from a mammoth carcass found frozen in the Siberian tundra in 2013.9
Patience, my young padawan cloner: there are obstacles that make de-extinction more difficult than cloning from living species. The somatic cells from which we take genetic material don't have to come from living bodies, but the egg cells into which we implant that genetic material have to be alive. Even if we could find living egg cells ready to receive genetic material from long-dead organisms, embryos don't simply grow up into mammoths, Zillo Beasts, or bounty hunters on their own. An embryo will only grow into a fully viable organism when it develops in the right environment, which is normally provided by the womb of a member of its own species. Dolly developed in the womb of another sheep. But where can we find a mammoth womb to clone a mammoth?
A tour of Kamino's cloning facilities reveals one possible solution. Boba Fett and his millions of cloned brethren in the Grand Army of the Republic were grown in artificial wombs. Grand Admiral Thrawn later found Spaarti “cloning cylinders” that served the same purpose: to create a developmental environment that resembles a living womb closely enough to produce a viable organism from an embryo.10 The success of Darth Sidious's plan to clone the Zillo Beast depended on his scientists' ability to create an artificial womb for that species. Human scientists haven't yet created an artificial womb. But rest assured: our finest Scottish geneticists and others around the world are working on it. We'll catch up with the Kaminoans soon enough. Once we do, it won't be long before the first clone of a mammoth trumpets its presence to the world.
Earth's scientists will probably create a woolly mammoth clone in the not-too-distant future, but will the clone be a woolly mammoth? This may seem like a silly question. After all, if an animal walks like a duck and talks like a duck, then it must be a duck. But don't forget the question posed by Luke Skywalker in the novelization of A New Hope: “What's a duck?”
What makes a duck a duck, a mammoth a mammoth, or a Zillo Beast a Zillo Beast? This is called the species problem, and it's one of the oldest in the philosophy of biology. It happens all the time: two biologists agree on all the observable facts about an organism, but still disagree about how to categorize that organism. The Star Wars galaxy has seen its share of these disputes, such as when the Encyclopedia Galactica controversially asserted that the Neimodian and Duros species were one and the same.11 One might point to the differences between the two – coloration, temperament, and so on – but the question of whether or not these add up to a difference in species remains open. What's a Neimoidian? That's a philosophical question.
It's commonly believed that organisms within different species have distinctive traits. Tigers have stripes, cheetahs have spots, Wookiees are tall, and Ewoks are short. Popular understanding of genetics holds that a species has a unique genetic code, which explains why humans have human babies and Ewoks have woklings. This way of defining species – by specifying some trait or set of traits unique to all and only members of the species – is called species essentialism, and it traces at least as far back as the famed Greek philosopher Aristotle (384–322 BCE).
Essentialism is the view that permits us to say that the Zillo Beast's clone would be a member of the Zillo Beast species. Since clones should be identical, the two organisms would have to share the same trait or set of traits unique to the Zillo Beast species. It's tempting to accept essentialism – if you've seen one Zillo Beast, you've seen 'em all – but biologists generally aren't essentialists these days. Instead, the predominant view in contemporary biology is that species evolve by natural selection, which is a view that conflicts with essentialism.
Evolution is any change in a species over time. Natural selection causes evolution by preserving beneficial variations within a species. In order for natural selection to work, the organisms within a species must vary from one another, they must be able to pass their variations on to subsequent generations, and some variations must give the organisms bearing them a better chance to reproduce than others. Ever since Charles Darwin (1809–1882) first proposed the theory, biologists have found that natural selection works so well because variability is a fundamental fact that is true of all species. If a species has evolved by natural selection – and it seems that all species have – then the species can't have an essence because there's no one trait or single set of traits common to all of its members. If natural selection is true, then species essentialism must be false.
Biologists now accept that species rise and species fall. They are born, they grow, and they die. In that sense, a species is like an individual organism. Individuals don't have essential traits because they grow and change throughout their lives. Consider Anakin Skywalker, who was by turns a precocious child, an obnoxious teen, a heroic young man, a terrifying human–machine hybrid, and an immaterial Force ghost. What makes Anakin the same individual through all that? Perhaps nothing more than the fact that Shmi Skywalker gave a name to her child at his birth and others continued to apply that name throughout his existence. As long as there is some connection to that origin, Anakin is Anakin. Contemporary philosopher Michael Ghiselin proposes that we should think of species in the same way: as individuals identified by their origins.12 This view is called species nominalism.
What makes a duck a duck, a mammoth a mammoth, and a Zillo Beast a Zillo Beast? Here's the nominalist answer: if each of those species has evolved by natural selection, then it can only be that ducks are connected to the particular origin of ducks, mammoths to the particular origin of mammoths, and Zillo Beasts to the particular origin of Zillo Beasts. There's no trait or set of traits – nothing we can point to or measure – that's common to all members of the species. There are only relations to other members of the species.
Perhaps you're wondering why any of this should be a problem for the prospects of de-extinction. Perhaps you see how Darth Sidious's Zillo Beast clone would be connected to the origin of all Zillo Beasts. This is one case in which your eyes can deceive you. Don't trust them. The species nominalist sees species as individuals. De-extinction is therefore resurrection, from a certain point of view. The tragedy of Darth Plagueis the Wise, when recounted by his apprentice Darth Sidious, implies that dead organisms could be resurrected through the dark side of the Force. Does the tragedy of the Zillo Beast imply that extinct species can be resurrected through cloning?
Species and organisms alike are born and grow and change, and so biologists consider species and organisms alike to be individuals. If cloning can resurrect extinct species – if SCNT can bring one kind of individual back from oblivion – then cloning should also be able to resurrect dead organisms. To see how effective a tool cloning can be for waking the dead, we can turn our attention to the Unknown Regions beyond the Star Wars galaxy's Outer Rim, to a planet in the Nirauan system. There's an outpost there whose five buildings resemble the fingers of a hand grasping for the stars. This outpost, called the “Hand of Thrawn” complex, is a cloning facility. The work done there has one goal: to bring Mitth'raw'nuruodo, also known as Grand Admiral Thrawn – heir to the Empire following the defeat of Darth Sidious – back from the dead.
Thrawn, ever the brilliant tactician, devised a plan to maintain control of the Empire even after meeting his proverbial destiny. He openly prophesied his return ten years after his apparent death, and then established the Hand of Thrawn complex to grow his own clone. The clone was programmed to wake one decade after the Grand Admiral's reported demise, and Grand Admiral Thrawn would be returned to life. If the scheme had worked, then it might be true, from a certain point of view, that Thrawn had been resurrected, but not from a point of view shared by any biologist. To understand why not, let's return to the cloning facilities on Kamino.
Forty years before Thrawn's clone prepared to awaken on Nirauan, the Kaminoans created Boba Fett through SCNT using Jango Fett's DNA. We can clearly see that Boba and Jango were different people. One could be on Kamino while the other stalked bounties on Coruscant. One sat in the passenger's seat of Slave I while the other sat in the pilot's seat. Boba watched as Jango was decapitated during the Battle of Geonosis. The experience scarred the young clone for life, and none of us need a degree in psychology to understand why: he watched his “father” die. There could be little comfort in the idea that Boba carried his father's entire DNA sequence. Jango Fett would remain dead and Boba Fett would remain alive because each was a unique person with a unique birth and subsequent life. The two, while qualitatively identical at the genetic level, were nonetheless numerically distinct as living organisms.
There really isn't much difference between Jango and Boba, on the one hand, and Thrawn and his clone, on the other. In both cases, one individual was the clone of the other. Yes, Boba lived at the same time as Jango, and no, Thrawn's clone didn't live at the same time as Thrawn, but this isn't a relevant difference. Thrawn's clone could've easily awoken too early, or Thrawn's death could've been mistakenly reported. Thrawn and his clone are clearly numerically distinct individuals in these cases. It's really only an historical accident that Thrawn did in fact die before his clone awoke, and so the clone should still be considered a numerically distinct organism – that is, someone other than Thrawn himself.
Resurrection requires more than the creation of an individual that bears a very strong, or even precise, resemblance to another individual that had previously died. An individual is only resurrected if that very same individual is somehow returned to life from death. This is what occurs when Emperor Palpatine returns, after his apparent death near Endor, in a younger cloned body.13 In this case, however, Palpatine survived his original body's death as a spectral form of dark side energy that comes to inhabit a cloned body. Thus, Palpatine remains the same person even though his cloned body is numerically distinct from the body Vader threw down the Death Star's reactor shaft. In Palpatine's case, cloning isn't what enabled his resurrection; it was dark side magic, which is a power that (thankfully) remains beyond the reach of any human science.
The comparison between the Fetts and the Thrawns shows that, in the case of organisms, cloning doesn't – and can't – resurrect anyone. Clones of an organism are always numerically distinct from the original organism, regardless of whether that organism is alive or dead at the time. This shouldn't come as too great a surprise since the original and its clone always have different births. Such is the case with organisms. What about species? Can the Zillo Beasts awake again?
Remember: organisms are considered individuals because they're identified by their births and subsequent life stories. An organism's death is a part of its unique life story, and so death is part of what identifies an individual organism. This is one the reasons that Jango, Boba, Thrawn, and Thrawn's clone are all numerically distinct individuals. Each has a unique origin, unique life story, and unique death. Remember also: species are considered individuals because they evolve by natural selection. They have origins, they grow, and they go extinct. The extinction of the Zillo Beasts is therefore a part of the species' unique “life story.”
If Darth Sidious were to succeed in cloning the last Zillo Beast, it would mark the origin of a new individual. What makes a Zillo Beast a Zillo Beast? From the biological point of view, it would be the organism's place in a sequence of events that starts with the species' birth on Malastare and ends with its extinction on Coruscant. Since the clone would be created after the extinction event, it must be that the clone falls outside the sequence that identifies the Zillo Beasts. Cloning can't resurrect extinct species because the philosophy of biology holds that extinct species stay extinct by definition. It's unknown whether Darth Sidious's plan to clone the last Zillo Beast ever succeeded. The Zillo Beast clone might have awoken. Nevertheless, the Zillo Beast species remains at rest, forever asleep.
Scientists on Earth currently debate whether the mammoth, an extinct species of elephant, can be resurrected through cloning. After pushing the idea of de-extinction to its limits in a galaxy far, far away, we now have an answer: no, not if the woolly mammoth species is an individual.
This doesn't mean we've philosophically disproven the possibility of cloning mammoths; nor does it mean that we've philosophically disproven that SCNT is a viable technology. All it means is that a mammoth clone wouldn't be a part of the same species as earlier, expired woolly mammoths, just as a Zillo Beast clone wouldn't be part of the same species as the last Zillo Beast who died on Coruscant. We'd therefore have to come up with new names for the species to which these clones belong.
The purpose of philosophy's far-fetched examples is to show which beliefs we want to keep and which we're willing to discard when those beliefs are carried to extremes. When we carry the idea of de-extinction to its logical extremes, we're forced to accept one of two mutually exclusive points of view. One is that de-extinction can't work because species are individuals. This point of view is determined by one's unwillingness to discard belief in the theory of natural selection. After all, it's a theory with an incredible amount of supporting evidence, not least of all the apparent genetic relation between Neimoidians and Duros.
The other point of view is that de-extinction can work. If one is unwilling to discard this belief, then species must be defined by unique traits. This requires seriously reconsidering one's understanding of the theory of natural selection. Following the works of contemporary philosophers Hilary Putnam and Saul Kripke, a group of philosophers calling themselves the “New Essentialists” recommend taking this route. The New Essentialists argue that essentialism can be compatible with natural selection if one looks beyond organisms' traits for species essences. Their work is gaining traction among philosophers, but hasn't convinced many biologists.14
Philosophical reflection leaves the choice of reconsidering de-extinction or reconsidering biological theory. You are free to make this choice, but you must do it alone. I cannot interfere. Can anyone help the mammoths or the Zillo Beasts? You must choose, but choose wisely.15